Hello, everyone, and FWIW I wanted to do a follow-up on my original
post. Although more expensive, I purchased a genuine IBM/Lenovo battery
(made in Japan using Sanyo Li-Ion batteries) from PCNation. It is
identical to the original in all respects and works as expected with the
ThinkPad A30 charging system. The Laptops for Less after-market battery
may have been usable but I couldn't get it to work properly with the
charging system even after trying upgrades and downgrades to the
Embedded Controller Program. There's just no substitute for the OEM
battery (at least for the A30), IMHO, even though it's more expensive.

I have had success with other non-ThinkPad laptop batteries from Laptops
for Less and they will give you an RMA and pre-paid return shipping
label if the battery is not compatible. So other than the time
involved, you might want to try a third-party battery first since they
are often considerably less expensive than the OEM one. Sincerely,